Ground gas is a wide-ranging term that includes landfill, methane, radon and shale gas. Because of the impacts of ground gas on the built environment, it is vital that site investigations and desktop studies are carried out before any development takes place.
Stephen Wielebski, principal partner of W A Consultancy Ltd and a CABE member, has specialised in the investigation and treatment/remediation of contaminated land for over 40 years. Stephen gave a very interesting and informative presentation to members in Newton-Ie-Willows Community Fire Station, which traced the progress that has been made on the understanding of this important issue.
On 23 May 1984, over 40 people gathered inside a valve house at the outfall end of the Lune/Wyre Water Transfer Scheme in Abbeystead for a public presentation. A catastrophic explosion occurred; tragically sixteen people were killed and nobody escaped uninjured. The subsequent inquiry determined that the explosion had been caused by the ignition of a mixture of methane and air, which had accumulated in the valve house.
In 1986 another explosion completely demolished a (luckily) unoccupied bungalow adjacent to a Derbyshire landfill site at Loscoe.
Following these and other emergencies, the Government, developers and the professions appreciated the need for investigations and surveys to check for the presence of ground gas. This resulted in the publication of regulations and much technical guidance dealing with the investigation into, treatment and monitoring of ground gas.
According to Stephen, there are approximately 4,000 such documents, which he warned included sensible but sometimes conflicting advice! He added that research has concluded that heavy rain, flooding and rising levels of ground water can have a significant effect on ground gas migration.
David Phythian, North West CABE Member
03 May 2018